Coiled spring contacts have been used in electrical applications as electrical contacts or means for transferring electric signals or energy between a pin and housing. Typically, such as in the case of canted-coil spring contacts, a length of coiled spring is joined at the ends to form a contact ring, where the pin contacts the canted-coil spring contact on the inside diameter of the contact ring and the housing contacts the spring contact on the outside diameter of the contact ring. The coils located between the pin and housing are able to deflect and thus maintain contact with the pin and the housing. However, as the size of the pin contacts decrease, such as reduce in diameter, producing such spring contacts become more challenging. Among other things, as the spring wire diameter gets smaller, the spring reduces strength and maintaining consistency in manufacturing is more difficult.
Canted coil springs for use in electrical contacts are typically sized limited to approximately three times the coil height. This limitation is typically the smallest ID of a welded spring.